Pontiac Fiero 1988 Service Manual page 601

6 E 3 - A - 1 8 DRIVABILITY A N D E M I S S I O N S - F U E L I N J E C T I O N ( P O R T )
ECM
RELAY
HARNESS
CONNECTOR
OSL PRESS.
I. P.
CONNECTOR
I —
ORN/BLK
FUELPUMP^
RELAY
440
N.O.
o
B A
o
J
o
G
o
J
TAN/WHT
TO
- • B A T T E R Y
FUEL PUMP 1 2 V
DK GRN/WHT 465
BLK/WHT 450
A1
D1
12 VOLT
RELAY DRIVE
ENGINE
GROUND
FUEL PUMP
(IN TANK)
ALDL CONNECTOR
5-19-87
15 W A Y I.P.
CONNECTOR
> H = £ t P S
A/AY — I —
3WAY
CONNECTOR
6-17-87
* 5 S 1 9 0 2 - 6 E
CHART A-7
(Page 2 of 4)
FUEL SYSTEM DIAGNOSIS
2.8L "P" SERIES (PORT)
Test Description:
Numbers below refer to circled
numbers on the diagnostic chart.
1. If the fuse is blown, this test will confirm a short to
ground on CKT 120. To prevent misdiagnosis, be
sure fuel pump is disconnected before test.
2. Determines if the pump circuit is ECM controlled.
The ECM will turn "ON" the pump relay. Engine
is not cranking or running so the ECM will turn
"OFF" the relay within 2 seconds after ignition is
turned "ON".
3. Turns "ON" the fuel pump if CKT 120 wiring is
OK. If the pump runs, it is a basic fuel delivery
problem which the following steps will locate.
4. Checks for battery voltage at the pump relay.
5. Checks relay ground CKT 450.